Former PetroSaudi International executive Xavier Andre Justo spent over five hours being interviewed by the Malaysian Anti-Corruption Commission yesterday in connection with its ongoing probe on 1MDB.

According to The Star, the Swiss national has also pledged to continue to help Malaysia in every way possible, including testifying in trials here.

"You need a person like me, who knows the chronology of events well and the persons involved in them, to filter the data.

"There is very important information like transaction documents that will be useful for the investigations, as well as private messages between employees that we do not need," he said.

The information was related to Justo's stint with PetroSaudi and a cache of some 230,000 emails which he obtained before leaving the company in 2011.

Justo had eventually handed over the cache to Sarawak Report editor Clare Rewcastle-Brown and a Malaysian media mogul in an attempt to recover some US$2 million owed to him by his former employer.

Following this, damning reports on how US$1 billion invested by 1MDB was abused began to surface, including how US$700 million was syphoned from the joint-venture with PetroSaudi, sparking domestic investigations on the deal.

"You must know that it happened nine years ago and it’s hard to go through all the e-mails from the hard drive.

"It’s something that takes years to read," Justo was quoted saying, adding that he could help as he already had "insider knowledge".

Justo was also seen in Malaysia late last month and held several meetings with Prime Minister Dr Mahathir Mohamad.

At the time, the newly formed 1MDB taskforce led by former MACC chief Abu Kassim Mohamed also confirmed that he had met with Justo in connection with its investigations.